Kinetics of endogenous mouse FEN1 in base excision repair.

The structure specific flap endonuclease 1 (FEN1) plays an essential role in long-patch base excision repair (BER) and in DNA replication. We have generated a fluorescently tagged FEN1 expressing mouse which allows monitoring the localization and kinetics of FEN1 in response to DNA damage in living cells and tissues. The expression of FEN1, which is tagged at its C-terminal end with enhanced yellow fluorescent protein (FEN1-YFP), is under control of the endogenous Fen1 transcriptional regulatory elements.

Mitochondrial DNA toxicity compromises mitochondrial dynamics and induces hippocampal antioxidant defenses.

Mitochondria are highly dynamic organelles that can be actively transported within the cell to satisfy local requirements. They are vital for providing cellular energy, but are also an important endogenous source of reactive oxygen species. The distribution of mitochondria is particularly important for neurons because of the morphological complexity of these cells, and because neural processing is metabolically expensive.